An electromagnetic wave going through vaccum is described by $E=E_0Sin (kx-ωt)$. $B = B_0Sin (kx – ωt)$ then:

$E_0k=B_0ω$

The correct answer is Option (1) → $E_0k=B_0ω$

Given that the electric field E and magnetic field B of an EM wave in a vacuum is,

$E=E_0\sin(kx-ωt)$

$B=B_0\sin(kx-ωt)$

and,

$E_0=cB_0$   ....(1)

$c=\frac{ω}{k}$   ....(2)

from (1) and (2)

$E_0k=ωB_0$